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Braquiópodos del Devónico de la zona de la sillimanita, en el monte Moosilauke, Nueva Hampshire
Science (New York, N.Y.)
|July 28, 1978
Resumen
Los braquiópodos del Devónico se encontraron en rocas altamente metamorfoseadas, ofreciendo un vínculo crucial para la comprensión de la estratigrafía de New Hampshire y Maine. Este descubrimiento proporciona nuevos conocimientos sobre las antiguas formaciones geológicas.
Área de la Ciencia:
- Paleontología Paleontología.
- Geología Geología Geología.
- La estratigrafía es la estratigrafía.
Sus antecedentes:
- Las rocas fosilizadas proporcionan datos críticos para comprender la historia geológica y las correlaciones estratigráficas.
- Las rocas de calcio-silicato representan un entorno geológico único donde la preservación de los fósiles puede ser un desafío debido a los procesos metamórficos y metasomáticos.
Objetivo del estudio:
- Para informar sobre el descubrimiento de braquiópodos devonianos en rocas de calcio-silicato de metamorfosis única.
- Para establecer un vínculo estratigráfico entre las rocas de las facies granulares en el centro de New Hampshire y las regiones fósiles en el oeste de New Hampshire y Maine.
Principales métodos:
- Muestreo geológico de campo e identificación de fósiles de braquiópodos a nivel genérico.
- Análisis petrográfico de rocas calcosilicatas para evaluar la intensidad metamórfica y metasomática.
- Correlación estratigráfica basada en ensamblajes fósiles y facciones rocosas.
Principales resultados:
- Recuperó con éxito braquiópodos del Devónico de rocas de calcio-silicato que exhiben metamorfismo y metasomatismo extremos.
- Los braquiópodos identificados son taxonómicamente significativos y se han conservado a pesar de la intensa alteración geológica.
- Estableció una conexión estratigráfica clave entre unidades geológicas dispares en New Hampshire y Maine.
Conclusiones:
- La presencia de braquiópodos del Devónico identificables en rocas altamente alteradas demuestra su resiliencia y potencial de preservación en entornos extremos.
- Estos fósiles sirven como fósiles de índice vital, permitiendo una correlación estratigráfica precisa entre regiones con diferentes grados metamórficos.
- Los hallazgos mejoran la comprensión de la historia geológica y la evolución estructural del orógeno de los Apalaches.
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